2013 年 12 巻 1 号 p. 16-29
Reactivity index is that theory which was developed at the right time to rational chemical bonding. Density Functional theory (DFT) has given precision to chemical concepts such as electro negativity, hardness, and softness and has embedded them in a perturbational approach to chemical reactivity. Since the majority of the reactions can be analyzed through the electrophilicity/nucleophilicity of various species involved, a proper understanding of these properties becomes essential. The hard soft acid-base (HSAB) principles classify the interaction between acids and bases in terms of global softness. In last few years the reactivity index methodology is well established and had found its application in a wide variety of systems. This study is to revisit the definition of reactivity index using density functional theory, within the domain of hard soft acid base (HSAB) principle and then to discuss its application in industrial applications; in combination with intra and intermolecular reactivity in materials.